1. Field of Invention
The present invention relates to a light effect system comprising at least one light source, which light source generates a beam of light, which beam of light is passing through a lens system which light effect system comprises at least one aperture element which aperture element comprises at least one aperture, which aperture comprises at least one light effect component.
The present invention further relates to a method for interchanging light effect elements in a lighting fixture, in which lighting fixture a beam of light is generated by a light source, which beam of light is passing through a lens system where the light beam is further passing through a light effect element which light effect element is placed in an aperture.
The present invention relates to automated lighting systems for use in entertainment, promotional, and architectural applications. Particularly, the invention relates to a system in e.g. a luminaire or projector where different optical components can easily be interchanged without using tools and without taking up space in the longitudinal direction.
2. Background
As general background, a description of an exemplary projector of the art is provided below. However, as may be appreciated, projectors in accordance with the invention include various other components and configurations. A projector of the prior art usually includes a light beam that emanates from a light source and a reflector at a first end of the projector. The beam passes through color filters before reaching gobo wheel of the projector. The gobo wheel is generally a single, drivingly rotatable wheel having multiple patterns etched therein and distributed about its outer periphery. In some projectors, a motor operated iris increases or decreases beam size before the beam encounters a motor operated effects wheel, which includes appropriate inserts mounted in peripherally distributed window apertures for creating desired modifying effects on the beam, such as altering beam pattern, color or diffusion, creating a prismatic effect, and the like. Finally, the projector may pass the light beam through one or more lenses for providing a zoom effect and for adjusting beam focus and/or divergence prior to exiting the projector housing. Components like gobos, color filters and prismatic lenses are in the following described as “optical components”
Conventional projectors for stage, theater, architectural, and display illumination include means for removably inserting various types of optical beam modifiers into the path of a light beam to vary the color, intensity, size, shape, and pattern of the beam. Thus, in a typical system, a light source produces white light which is passed, for example, through at least one color filter wheel for producing a colored light beam, a gobo wheel for imposing a selected pattern on the light beam, a light intensity wheel for varying the intensity of the light transmitted there through, a mechanical iris for determining beam size, and a lens system for controlling light beam focus and divergence. U.S. Pat. No. 4,392,187 to Bornhorst discloses several such systems. For imposing a desired pattern on the light beam, it is well known to pass the beam through a gobo, which is a template or a light stencil having a predetermined pattern. Typically, gobos are formed by chemically etching the desired pattern onto stainless steel discs. The gobos discs are usually supported in the projected light beam to impose upon the light passing there through the pattern which has been etched into the discs.
It is well known, for example from U.S. Pat. No. 4,460,943 to Callahan, to provide a mounting plate having a plurality of equally spaced apertures arranged around a common axis for mounting gobos within one or more of the apertures. The plate is drivingly rotatable, such as via a motor, about its axis to insert a selected gobo into the path of the beam of light.
U.S. Pat. No. 4,891,738 to Richardson discloses a similar arrangement including an apertured gobo mounting plate which is rotatably driven by motor driven rollers frictionally engaging the peripheral edge of the plate. The gobos are mounted on or within holders which, in turn, are fixedly positioned within the plate apertures. The mounting plate is rotatably driven to position a selected gobo within the beam of light. After reaching this position, a motor-operated holder drive mechanism acts, through frictional contact with the rim of the holder, to rotatably drive the gobo holder in either direction at various speeds. In this manner, the plate is rotatable to position a selected gobo within the beam of light, and the gobo holder is rotatable to spin the gobo holder within the beam of light.
Generally, the projectors are constructed in a compact fashion because the rotational inertia of the projector increases the speed at which the beam of light can be moved into position. Furthermore, in an optical system, there will always be a limited room for focusing. This means that the optical components like gobos, which are supposed to be projected, only have very limited room, and it is crucial to have as many optical components in this area as possible in order to have the most interesting product. This compact design leads to various disadvantages in the maintenance and upkeep of the projectors. Furthermore, the compact design of the projectors hinders the replacement of gobos in the projector.
For example, U.S. Pat. No. 5,402,326 to Belliveau discloses a gobo carousel that contains a number of gobo holders. The carousel is rotatable to position a desired gobo within the light path and further includes means for rotating the holders in relation to the carousel itself. The holders are permanently attached to the carousel and include a mechanism for securely retaining and for replacing gobos from within the holders. However, due to the compact design of the light projector, such gobo carousels, as well as the gobo holders, are often mounted in close proximity to adjacent mechanical parts. Accordingly, replacing the gobos in the gobo holders can be very awkward.
This is in many aspects solved in U.S. Pat. No. 6,601,973 to Rasmussen which discloses an interchangeable gobo wheel assembly including a plurality of apertures and gobo holders containing gobos. The gobo wheel is adapted to rotate so as to place a gobo, which is retained in one of the holders, within the light path from the light source. The gobo holders of the gobo wheel are removably secured to the gobo wheel by a spring retainer that engages flange portions of a gobo holder. This system has the disadvantage that the optical element (here a gobo in a gobo holder) has to be slightly angled to be released from its position, and this open space may not be an option in compact lighting fixture designs.
Therefore, there is need for a system that enables easy exchange of optical components (e.g. gobos) in such compactly constructed projector without the need of reserving space in the longitudinal direction in the fixture.